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Adjusts YouTube quality when not focused
Automatically lowers YouTube quality when the script detects that tab is no longer in-view/focused.
Settings must be changed in the script for now.
That slight pause every time the quality is changed is unfortunately not going away any time soon.
YouTube keeps your quality settings cached, so it will start at 144p if you closed the tab while in the background. Just click another tab and go back. (ot fixed due to browser inconsistencies in detecting resets)